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Liufu S, Lan Q, Liu X, Chen B, Xu X, Ai N, Li X, Yu Z, Ma H. Transcriptome Analysis Reveals the Age-Related Developmental Dynamics Pattern of the Longissimus Dorsi Muscle in Ningxiang Pigs. Genes (Basel) 2023; 14:genes14051050. [PMID: 37239410 DOI: 10.3390/genes14051050] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2023] [Revised: 05/02/2023] [Accepted: 05/04/2023] [Indexed: 05/28/2023] Open
Abstract
The growth and development of the Longissimus Dorsi muscle are complex, playing an important role in the determination of pork quality. The study of the Longissimus Dorsi muscle at the mRNA level is particularly crucial for finding molecular approaches to improving meat quality in pig breeding. The current study utilized transcriptome technology to explore the regulatory mechanisms of muscle growth and intramuscular fat (IMF) deposition in the Longissimus Dorsi muscle at three core developmental stages (natal stage on day 1, growing stage on day 60, and finishing stage on day 210) in Ningxiang pigs. Our results revealed 441 differentially expressed genes (DEGs) in common for day 1 vs. day 60 and day 60 vs. day 210, and GO (Gene Ontology) analysis showed that candidate genes RIPOR2, MEGF10, KLHL40, PLEC, TBX3, FBP2, and HOMER1 may be closely related to muscle growth and development, while KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis showed that DEGs (UBC, SLC27A5, RXRG, PRKCQ, PRKAG2, PPARGC1A, PLIN5, PLIN4, IRS2, and CPT1B) involved the PPAR (Peroxisome Proliferator-Activated Receptor) signaling pathway and adipocytokine signaling pathway, which might play a pivotal role in the regulation of IMF deposition. PPI (Protein-Protein Interaction Networks) analysis found that the STAT1 gene was the top hub gene. Taken together, our results provide evidence for the molecular mechanisms of growth and development and IMF deposition in Longissimus Dorsi muscle to optimize carcass mass.
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Affiliation(s)
- Sui Liufu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Qun Lan
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xiaolin Liu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Bohe Chen
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xueli Xu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Nini Ai
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Xintong Li
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Zonggang Yu
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
| | - Haiming Ma
- College of Animal Science and Technology, Hunan Agricultural University, Changsha 410128, China
- Guangdong Laboratory for Lingnan Modern Agriculture, Guangzhou 510642, China
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Jiang DL, Zhou XL, Xu YL, Liufu S, Fu XL, Xu DN, Tian YB, Shen X, Huang YM. Effects of stocking density on ovarian development and maturation during the rearing period in Shan-ma ducks. Poult Sci 2022; 101:101809. [PMID: 35358924 PMCID: PMC8968648 DOI: 10.1016/j.psj.2022.101809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2021] [Revised: 02/10/2022] [Accepted: 02/22/2022] [Indexed: 12/24/2022] Open
Abstract
Stocking density critically affects the growth and subsequent performance of animals in modern poultry production. This study investigated the effects of stocking density on ovarian development, ovarian maturation, and the mRNA expression of key genes in the reproductive axis during the rearing period of Shan-ma ducks. The experiments involved 180 healthy 7-wk-old Shan-ma ducks and randomly divided into low stocking density (LSD; n = 30, density = 5 birds/m2), medium stocking density (MSD; n = 60, density = 10 birds/m2) and high stocking density groups (HSD; n = 90, density = 15 birds/m2), for rearing. After examining ovarian development and measuring hormone levels in the plasma and expression levels of key regulatory genes in the reproductive axis at 19 wk of rearing, analysis of the gonad index analysis, reflecting stocking density, uncovered statistically significant differences. The gonad index of the LSD group was significantly higher than those of the MSD and HSD groups (P < 0.01), while no significant difference was observed between the MSD and HSD groups. pre-ovulatory follicles (POFs) and small yellow follicles (SYFs) development was only apparent in the LSD group, with the large white follicles (LWFs) number of this group being significantly higher than that of the MSD group (P < 0.05). The blood levels of E2 (estradiol), P4 (progesterone), and T (testosterone) were significantly higher in the LSD group than in the MSD and HSD groups (P < 0.05 or 0.01). Also, the levels of both P4 and T were significantly higher in the MSD group than in the HSD group (P < 0.01). The gene expression levels of GnRHR, FSH, AMHR, and FSHR were significantly increased in the LSD group compared to the MSD and HSD groups (P < 0.05 or 0.01), while the expression levels of GnIHR and GDF9 were significantly decreased in the LSD and MSD groups compared to the HSD group (P < 0.05 or 0.01). Steroid biosynthesis pathway genes such as StAR, CYP11A1, 3β-HSD, CYP19A1, and BMP15 were significantly downregulated at greater stocking densities (P < 0.05 or 0.01). Likewise, the protein expression of StAR, 3β-HSD, and CYP19A1 was also significantly decreased (P < 0.05 or 0.01). These results demonstrate that both medium and high stocking densities suppressed the expression of the key reproduction-promoting factors, while the expression level of the key reproductive inhibitory factors was enhanced. Therefore, rates of ovarian development and maturation could be reduced by a high stocking density leading to a delay in reproduction performance during the rearing period of Shan-ma ducks.
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Affiliation(s)
- Dan-Li Jiang
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Xiao-Li Zhou
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Yang-Long Xu
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Sui Liufu
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Xin-Liang Fu
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Dan-Ning Xu
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Yun-Bo Tian
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Xu Shen
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China
| | - Yun-Mao Huang
- College of Animal Science & Technology, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China; Guangdong Province Key Laboratory of Waterfowl Healthy Breeding, Guangzhou, Guangdong 510225, China.
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Montoro-Dasi L, Villagra A, Vega S, Marin C. Influence of farm management on the dynamics of Salmonella enterica serovar Infantis shedding and antibiotic resistance during the growing period of broiler chickens. Vet Rec 2021; 188:e302. [PMID: 33870529 DOI: 10.1002/vetr.302] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 11/26/2020] [Accepted: 03/07/2021] [Indexed: 11/10/2022]
Abstract
BACKGROUND Salmonella enterica serovar Infantis is a zoonotic pathogen isolated in broilers causing great economic losses in the European poultry sector. It is demonstrated that an investment in management measures at farm level could directly affect the control of food chain microorganisms. The aim of this study was to investigate the development of S. Infantis antimicrobial resistance (AMR) patterns during the growing period, according to flock density and ventilation management, without antibiotic administration. METHODS The experiment was performed in two identical poultry houses, evaluating commercial and optimal farm conditions. At 24 h of rearing, 20% of the animals were orally infected with a S. Infantis strain susceptible to all the antibiotics tested. To study Salmonella shedding, faeces samples from each experimental group were taken weekly and analysed as per ISO/TS 6579-2:2017. Antibiotic susceptibility was assessed according to Decision 2013/653. RESULTS Salmonella shedding showed that the lowest counts were observed in the first week post-infection and highest at slaughter day for both groups. Moreover, 100% of the isolates were multi-resistant. CONCLUSION The acquisition of AMR by S. Infantis starts at the onset of the production cycle and is maintained until the end, demonstrating the importance of transmission of AMR in zoonotic bacteria at farm level.
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Affiliation(s)
- Laura Montoro-Dasi
- Instituto de Ciencia y Tecnología Animal, Universidad Politécnica de Valencia, Valencia, Spain.,Centro de Calidad Avícola y Alimentación Animal de la Comunidad Valenciana (CECAV), Castellón, Spain
| | - Arantxa Villagra
- Centro de Investigación y Tecnología Animal, Instituto Valenciano de Investigaciones Agrarias, Castellón, Spain
| | - Santiago Vega
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Instituto de Ciencias Biomédicas, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Moncada, España
| | - Clara Marin
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Instituto de Ciencias Biomédicas, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Moncada, España
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Montoro-Dasi L, Villagra A, de Toro M, Pérez-Gracia MT, Vega S, Marin C. Assessment of Microbiota Modulation in Poultry to Combat Infectious Diseases. Animals (Basel) 2021; 11:615. [PMID: 33652795 DOI: 10.3390/ani11030615] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2021] [Revised: 02/13/2021] [Accepted: 02/23/2021] [Indexed: 11/26/2022] Open
Abstract
Simple Summary This research was designed to evaluate the differences in caecal microbiota in broilers reared under two different farm conditions (commercial vs. optimal) during the growing period, using 16 rRNA sequencing analysis. Microbiota composition is affected by stress; for this reason, it could be considered a biomarker of poultry welfare and health. The main results demonstrated that no statistically significant differences were found between groups on microbiota composition from the beginning to the mid-period. However, significant differences were found at the end of growing, when a higher level of microbiota diversity was observed in the optimal farm conditions group. In conclusion, microbiota composition could be an interesting tool to evaluate new management conditions at field level, and could be developed to improve animal welfare during the growing period. Abstract Poultry is one of the main agricultural sub-sectors worldwide. However, public concern regarding animal welfare and antimicrobial resistance has risen in recent years. Due to the influence of management practices on microbiota, it might be considered to evaluate poultry welfare and health. Therefore, the objective of this research was to analyse the influence on microbiota balance of broilers under commercial and optimal farm conditions, using 16S rRNA sequencing analysis. The research was performed in two identical poultry houses (commercial vs. optimal). Results showed a higher level of microbiota complexity in the group reared under optimal farm conditions at the end of rearing. Regarding microbiota composition, Firmicutes was the dominant phylum during the entire growing period. However, the second most prevalent phylum was Proteobacteria at the arrival day, and Bacteroidetes from the mid-period onward in both groups. Moreover, the most predominant genera identified were Oscillospira, Ruminococcus, Bacteroides, and Coprococcus. In conclusion, it is necessary to optimize farm management as much as possible. Using gut microbiota diversity and composition as biomarkers of animal health could be an important tool for infectious disease control, with the aim of reducing the administration of antibiotics at field level.
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Montoro-Dasi L, Villagra A, de Toro M, Pérez-Gracia MT, Vega S, Marin C. Fast and Slow-Growing Management Systems: Characterisation of Broiler Caecal Microbiota Development throughout the Growing Period. Animals (Basel) 2020; 10:ani10081401. [PMID: 32806542 PMCID: PMC7459849 DOI: 10.3390/ani10081401] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2020] [Revised: 08/08/2020] [Accepted: 08/10/2020] [Indexed: 12/24/2022] Open
Abstract
Simple Summary This study was conducted to characterise the caecal microbiota in two broiler management systems (fast and slow-growing) during the growing period, using 16S rRNA sequencing analysis. Because of the essential role of the caecal bacteria in poultry health and productivity, these data could be considered as a biomarker of health status and will make it possible to evaluate different treatments applied in animals. The main results demonstrated that microbiota is in constant development throughout the growing period for both management systems, and the most abundant bacteria groups are related to better productive performance and intestinal health. Abstract Caecal microbiota and its modulation play an important role in poultry health, productivity and disease control. Moreover, due to the emergence of antimicrobial-resistant bacteria, society is pressing for a reduction in antibiotic administration by finding effective alternatives at farm level, such as less intensified production systems. Hence, the aim of this study was to characterise the caecal microbiota in two different broiler management systems, fast and slow-growing, using 16S rRNA sequencing analysis. To this end 576 broilers were reared in two different management systems (fast and slow-growing). Results showed that Firmicutes represented the dominant phylum for both systems. At the onset, Proteobacteria was the second prevalent phylum for fast and slow-growing breeds, outnumbering the Bacteroidetes. However, during the rest of the production cycle, Bacteroidetes was more abundant than Proteobacteria in both groups. Finally, regardless of the management system, the most predominant genera identified were Oscillospira spp., Ruminococcus spp., Coprococcus spp., Lactobacillus spp. and Bacteroides spp. In conclusion, fast and slow-growing broiler microbiota are in constant development throughout rearing, being relatively stable at 21 days of age. Regarding the genus, it should be noted that the three most abundant groups for both systems, Ruminococcus spp., Lactobacillus spp. and Bacteroides spp., are related to better productive performance and intestinal health.
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Affiliation(s)
- Laura Montoro-Dasi
- Instituto de Ciencia y Tecnología Animal, Universidad Politécnica de Valencia, 46022 Valencia, Spain;
- Centro de Calidad Avícola y Alimentación Animal de la Comunidad Valenciana (CECAV), 12539 Castellón, Spain
| | - Arantxa Villagra
- Centro de Investigación y Tecnología Animal, Instituto Valenciano de Investigaciones Agrarias, 12400 Castellón, Spain;
| | - María de Toro
- Plataforma de Genómica y Bioinformática, Centro de Investigación Biomédica de La Rioja, 26006 La Rioja, Spain;
| | - María Teresa Pérez-Gracia
- Área de Microbiología, Departamento de Farmacia, Instituto de Ciencias Biomédicas, Facultad de Ciencias de la Salud, Universidad Cardenal Herrera-CEU, CEU Universities, Avenida Seminario s/n, 46113 Moncada, Spain;
| | - Santiago Vega
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Instituto de Ciencias Biomédicas, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Avenida Seminario s/n, 46113 Moncada, Spain;
| | - Clara Marin
- Departamento de Producción y Sanidad Animal, Salud Pública Veterinaria y Ciencia y Tecnología de los Alimentos, Instituto de Ciencias Biomédicas, Facultad de Veterinaria, Universidad Cardenal Herrera-CEU, CEU Universities, Avenida Seminario s/n, 46113 Moncada, Spain;
- Correspondence: ; Tel.: +34-657-506-085
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Wei Y, Zheng W, Li B, Tong Q, Shi H. Effects of a two-phase mixed color lighting program using light-emitting diode lights on layer chickens during brooding and rearing periods. Poult Sci 2020; 99:4695-4703. [PMID: 32988504 PMCID: PMC7598341 DOI: 10.1016/j.psj.2020.06.072] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2020] [Revised: 05/17/2020] [Accepted: 06/08/2020] [Indexed: 11/01/2022] Open
Abstract
The behavior, growth and development, and production performance of poultry are affected by the light environment. The influence of light results from a combination of light sources, light intensity, light color, and the photoperiod regimen. With light-emitting diode (LED) lamps applied in poultry housing systems, specific light colors are desired for each time period for layer chickens. The objective of this study was to investigate the effects of a 2-phase mixed color lighting program (phase 1: blue-green, 1 D-13 wk; phase 2: yellow-orange, 14-20 wk) using LED lights on the blood parameters, skeletal development parameters, and sexual development parameters of caged layer chickens during their brooding and rearing periods. Fifty-two chickens were raised from 1 D to 20 wk of age in each of the 4 treatment groups with 3 replicates, with white (400-700 nm) light at phase 1 and phase 2 (WL treatment as the control); blue-green (435-565 nm) light at phase 1 followed by yellow-orange (565-630 nm) light at phase 2 (BG-YOL treatment); yellow-orange LED (565-630 nm) light at phase 1 and phase 2 (YOL treatment); and blue-green (435-565 nm) light at phase 1 and phase 2 (BGL treatment). The results showed that the serum Ig concentrations of the layer chickens in the BG-YOL treatment and BGL treatment were higher than those in the WL treatment at 13 wk of age (P < 0.05). At the age of 20 wk, the serum glucose concentration levels of the pullets after the WL and BGL treatments were lower than those after the YOL treatment (P < 0.05). Compared with the WL treatment, the YOL treatment significantly increased the bone mineral density of the layer chickens (P < 0.05), and BG-YOL treatment promoted the development of the sexual organs (oviducts and ovaries) of the laying hens at the age of 20 wk (P < 0.05). For the 50% egg production age, the YOL treatment was earlier than the other 3 treatments. This study demonstrated that appropriately staged spectral control using LED lights could have positive effects on the immune performance, bone development, and production performance of caged layer chickens during their brooding and rearing periods.
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Affiliation(s)
- Yongxiang Wei
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs of China, Beijing 100083, China; Beijing Engineering Research Center on Animal Healthy Environment, China Agricultural University, Beijing 100083, China
| | - Weichao Zheng
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs of China, Beijing 100083, China; Beijing Engineering Research Center on Animal Healthy Environment, China Agricultural University, Beijing 100083, China.
| | - Baoming Li
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs of China, Beijing 100083, China; Beijing Engineering Research Center on Animal Healthy Environment, China Agricultural University, Beijing 100083, China
| | - Qin Tong
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs of China, Beijing 100083, China; Beijing Engineering Research Center on Animal Healthy Environment, China Agricultural University, Beijing 100083, China
| | - Haipeng Shi
- Department of Agricultural Structure and Environmental Engineering, College of Water Resources & Civil Engineering, China Agricultural University, Beijing 100083, China; Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture and Rural Affairs of China, Beijing 100083, China; Beijing Engineering Research Center on Animal Healthy Environment, China Agricultural University, Beijing 100083, China
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Montoro-Dasi L, Villagra A, Sevilla-Navarro S, Pérez-Gracia MT, Vega S, Marin C. The dynamic of antibiotic resistance in commensal Escherichia coli throughout the growing period in broiler chickens: fast-growing vs. slow-growing breeds. Poult Sci 2020; 99:1591-7. [PMID: 32111325 DOI: 10.1016/j.psj.2019.10.080] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Revised: 10/30/2019] [Accepted: 10/30/2019] [Indexed: 12/13/2022] Open
Abstract
Antimicrobial resistance (AMR) is an important threat to public health worldwide. Furthermore, different studies have demonstrated a close association between antibiotic use in animal production and AMR in humans. It is well known that it is necessary to reduce antibiotic administration in farms by finding effective alternative treatments, using more resistant breeds and improving animal welfare. However, to be able to assess the alternatives proposed, it is essential to study the epidemiology of AMR under production conditions. Hence, the aim of this study was to investigate the AMR dynamic in 2 genetic poultry breeds during the growing period. The study was performed in 2 experimental poultry houses to simulate real production conditions, and no antibiotics were administered during the growing period. In addition, 2 poultry breeds were used, fast-growing and slow-growing. To evaluate AMR evolution, Escherichia coli was selected as indicator bacterium. To this end, animals from each experimental group were sampled at different times: on day of arrival, at mid-period, and at slaughter day. In the laboratory, cecal content was removed and inoculated in selective media. Then, biochemical tests were performed to confirm E. coli. Finally, antibiotic susceptibility was assessed according to Decision 2013/653. At the onset of the cycle, significant differences were observed between breeds, as the E. coli strains isolated from fast-growing 1-day-old-chicks showed higher AMR rates. However, at the end of the period, no significant differences were found between breeds and their presence of resistant bacteria (above 95%). Therefore, although no antibiotics were administered during the growing period, a high level of AMR at slaughter day was demonstrated. Further studies are necessary to determine the main risk factors that increase the level of AMR throughout the productive cycle in broiler chickens. In conclusion, it is important to highlight that although it is crucial to control both antibiotic use and animal welfare during the growing period, measures should be taken at all levels of the production chain.
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Abstract
This study was to investigate the influences of habitual mouth breathing on memory and learning ability during the growth period. At age 5 weeks, the experimental rats were subjected to surgery to close completely one side of the nasal cavity. An 8-arm radial maze was used to evaluate memory and learning ability at age 7, 11, and 15 weeks. Moreover, the brain was extracted at age 7, 11, and 15 weeks, and subjected to histomorphometric examination for the distribution and number of pyramidal cells in the hippocampal CA1 and CA3 regions after Nissl staining. The trial time to accomplish each task was significantly longer in the experimental group than in the control group throughout the experimental period. The number of pyramidal cells was significantly less in the experimental rats than in controls in both the CA1 and CA3 regions for the entire experimental period. Thus, the functional deterioration of the respiratory system during the growth phase exerts a substantial effect on the growth and development of the central nervous system.
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Affiliation(s)
- Noriko Tsubamoto-Sano
- Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences
| | | | - Hiroshi Ueda
- Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences
| | - Masato Kaku
- Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences
| | - Kazuo Tanne
- Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences
| | - Kotaro Tanimoto
- Department of Orthodontics, Applied Life Sciences, Hiroshima University Institute of Biomedical & Health Sciences
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